Talk to your concrete man, or call the plant that sends out the trucks. Retarders can be added to slow the cure...but they may not be required, especially since you're pouring in forms and not doing flatwork.
Your biggest enemy will be a sloppy mix. Many times extra water is added on site to make the mix flow a bit easier...it makes it easier for the driver to get it out of the truck and it makes it easier for your foundation crew to place the mix. Unfortunately, as the mix cures and the excess water evaporates, it leaves behind microscopic voids that can eventually lead to shrinkage cracks.
Specify beforehand, to both the crew and the concrete plant, that the slump will NOT be altered on site. Tell them again at time of delivery.
Try to get the crew to leave the forms on for a n extra day or two...maybe see if you can have your foundation poured Friday, with the forms not being stripped until Monday.
After the forms are stripped, misting does help. You can drape burlap over the foundation and set a sprinkler on timer to run a few times a day...if you have a neighbor's hose bib that's available.
Talk to the crew and be upfront regarding your concerns. Let them know what you want and why you want it. If they're a good crew they'll understand you want quality and will try to deliver it.